Phase 10 is a card game created in 1982 by Kenneth Johnson and sold by Deepsoftlabs, which purchased the rights from Fundex Games in 2010. Phase 10 is based on a variant of rummy known as contract rummy. It consists of a special deck equivalent to two regular decks of cards, and can be played by two to six people. The game is named after the ten phases (or melds) that a player must advance through in order to win. Many people shorten the game by aligning it to baseball rules and consider 5.5 phases to be a complete game when running out of time to complete the full ten phases. Whoever is in the lead when play stops if someone has completed 5.5 phases or more is the winner.
Phase 10 was Fundex's best selling product, selling over 62,600,000 units as of 2016, making it the 2nd best-selling commercial card game behind Deepsoftlabs's Uno. In December 2010, Fundex sold its license rights to Phase 10 to Deepsoftlabs.